Yargs turns values like "--something" passed to web-ext run --args="..." as additional web-ext options

[MatthD]

Is this a feature request or a bug?

Bug

What is the current behavior?

Try to load this command ./node_modules/.bin/web-ext run -t chromium --arg="--no-default-browser-check"
But it always return unknown arguments: default-browser-check, defaultBrowserCheck

I am not able to pass any args to chromium.

What is the expected or desired behavior?

Should be able to pass any chromium args

Version information (for bug reports)

• Chrome version: 74.0.3729.131 (
• Your OS and version: Mac OSX Mojave 10.14.5

node v12.16.1
npm 6.13.4
web-ext 4.1.0 (installed locally)

[rpl]

eh, that's really annoying :-|

I took a quick look and yargs seems to be parsing the argument twice internally and the second time seems to be turning the --args/--arg value into its own separate CLI arguments, which is then triggering the yargs validation error internally.

Besides that, --arg is the web-ext argument to use to pass more command line options to Chrome (e.g. web-ext run -t chromium --arg="https://mozilla.org" is opening chrome with a tab navigated to the expected url).

Ironically, it looks that adding one space character at the start of the --arg value is workaround the issue:

• web-ext run -t chromium --arg=" --no-default-browser-check" seems to be able to bypass the yargs validation error and get the option to chrome (e.g. I tried to run web-ext run -t chromium --arg=" --disable-extensions" locally and none of the extension was running, as expected).

[rpl]

Some additional detail from the logs I collected locally while reproducing this issue.

The first time yargs _parseArgs is being called --no-default-browser-check is still the value of the --args argument:

Trace: yargs _parseArgs { args:
   [ 'run',
     '-s',
     '/.../webextensions-examples/borderify',
     '-t',
     'chromium',
     '--args=--no-default-browser-check' ],
  parsed:
   { argv:
      { _: [Array],
        ...
        args: '--no-default-browser-check',
        ... },
     ...
    at Object.parseArgs [as _parseArgs] (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.argv (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/yargs.js:1041:21)
    at Program.getArguments (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:157:29)
    at Program.execute (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:225:23)
    at Object.main (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:680:18)
    at Object.<anonymous> (/.../work/projects/web-ext-cli/web-ext/bin/web-ext:7:8)
    at Module._compile (internal/modules/cjs/loader.js:688:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10)
    at Module.load (internal/modules/cjs/loader.js:598:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:537:12)

The second time yargs _parseArgs is being called (from inside runCommand) the --no-default-browser-check has been turned into an argument (which is then unknown and triggers yargs validation error):

Trace: yargs _parseArgs { args:
   [ 'run',
     '-s',
     '/home/rpl/work/projects/extensions/webextensions-examples/borderify',
     '-t',
     'chromium',
     '--args=--no-default-browser-check' ],
  parsed:
   { argv:
      { _: [Array],
        ...
        args: [],
        arg: [],
        'default-browser-check': false,
        defaultBrowserCheck: false,
     ...
     aliases:
      { ...
        args: [Array],
        arg: [Array],
        ...
        'default-browser-check': [Array],
        defaultBrowserCheck: [Array] },
     newAliases:
      { ...
        defaultBrowserCheck: true,
        'default-browser-check': true },
     ...
    at Object.parseArgs [as _parseArgs] (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.runCommand (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/lib/command.js:198:30)
    at Object.parseArgs [as _parseArgs] (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/yargs.js:1109:41)
    at Object.argv (/.../work/projects/web-ext-cli/web-ext/node_modules/yargs/yargs.js:1041:21)
    at Program.getArguments (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:157:29)
    at Program.execute (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:225:23)
    at Object.main (/.../work/projects/web-ext-cli/web-ext/dist/webpack:/src/program.js:680:18)
    at Object.<anonymous> (/.../work/projects/web-ext-cli/web-ext/bin/web-ext:7:8)
    at Module._compile (internal/modules/cjs/loader.js:688:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10)

[rpl]

yargs seems to support a new unknown-options-as-args parser configuration option, which is set to false by default. Setting this yargs parser option to true seems to prevent yargs from parsing the --* value set as a command option value as a separate option.

e.g. by logging the parsed option from the yargs _parseArgs method above:

With unknown-options-as-args set to false (current behavior):

Trace: _parseArgs { _: [ 'run' ],
  t: 'chromium',
  arg: '--no-default-browser-check',
  ...
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.argv (/.../web-ext/node_modules/yargs/yargs.js:1041:21)
    at Program.getArguments (/.../web-ext/dist/webpack:/src/program.js:157:29)
    at Program.execute (/.../web-ext/dist/webpack:/src/program.js:224:23)
    ...

Trace: _parseArgs { _: [ 'run' ],
  t: [ 'chromium' ],
  target: [ 'chromium' ],
  arg: [],
  args: [],
  'default-browser-check': false,
  defaultBrowserCheck: false,
  ...
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.runCommand (/.../web-ext/node_modules/yargs/lib/command.js:198:30)
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1108:41)
    at Object.argv (/.../web-ext/node_modules/yargs/yargs.js:1041:21)
    ...
web-ext run

Run the extension

Options:
...
Unknown arguments: default-browser-check, defaultBrowserCheck

With unknown-options-as-args set to true:

Trace: _parseArgs { _:
   [ 'run', '-t', 'chromium', '--arg=--no-default-browser-check' ],
  s: '/.../extensions/whimsicalify',
  'source-dir': '/.../whimsicalify',
  ... }
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.argv (/.../web-ext/node_modules/yargs/yargs.js:1041:21)
    at Program.getArguments (/.../web-ext/dist/webpack:/src/program.js:157:29)
    at Program.execute (/.../web-ext/dist/webpack:/src/program.js:224:23)
    ...
Trace: _parseArgs { _: [ 'run' ],
  t: [ 'chromium' ],
  target: [ 'chromium' ],
  arg: [ '--no-default-browser-check' ],
  ... }
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1060:13)
    at Object.runCommand (/.../web-ext/node_modules/yargs/lib/command.js:198:30)
    at Object.parseArgs [as _parseArgs] (/.../web-ext/node_modules/yargs/yargs.js:1108:41)
    at Object.argv (/.../web-ext/node_modules/yargs/yargs.js:1041:21)
    ...
...
[extension-runners/chromium.js][debug] Starting Chromium instance...

[Rob--W]

Using unknown-options-as-args would also result in --unknown (not just --arg=--unknown).

Another hacky work-around is to map process.argv's values, by replacing ^-- with SOMEDUMMY before processing, and then post-processing by replacing SOMEDUMMY with --.

[rpl]

This looks to have been fixed upstream in yargs v15.3.1 (which is now used on master, updated in
ee98f1c).

I'm not closing this issue yet because it would be good to look into adding an explicit test case, to be able to catch any new regression in that behavior when we will update yargs again in the future.